JP2019048128A - Device, system, and method for heartbeat signal detection and processing - Google Patents

Abstract

To provide a system capable of assuring satisfactory detection of a heartbeat even when there is interference caused by various generation sources.SOLUTION: A heartbeat detection device includes at least one optical reflection sensor (10 or 10a and 10b) to be placed on the skin of a person. A sensor unit is provided with a light emitter (11) and a corresponding light receiver (12) for converting a light reflected by the skin to an electric signal, includes electrically adjustable optical filters (16 and 17) connected to the light emitter or the light receiver, or both of them, for selecting desired light wavelength when operated, and executes processing of the signal thus obtained for reinforcing a heartbeat signal. There are descriptions on the system having this device, and the detection method as well.SELECTED DRAWING: Figure 1

Description

  The present invention relates to innovative devices, systems and methods for detecting heart beats.

  An optically functional heart beat detection system (BVP (Blood Volume Pulse)) detection system is known. Such systems typically use a light emitter that illuminates a suitable receiver by reflection or transmission after the radiation has impinged on or passed through a zone of the body.

  Basically, such a heart rate monitor is a detection system that can measure how blood volume changes over time in a specific zone of the body.

  In general, reflective devices are placed in certain zones of the body, such as the wrist, where the amount of light reflected is dependent on the superficial blood flow in that zone. Instead, the transmission device is applied near a relatively thin part of the body (such as a finger or an earlobe) to allow light to pass through it, detecting changes in the light passing by the blood flow in said part.

  However, both systems are susceptible to disturbances of the useful signal, for example due to both ambient light conditions and the movement of the person receiving the measurement.

  For example, the sensor functions by contact with the deformable medium through which blood flows, i.e. the skin. This medium impairs the measurement and is subject to unwanted signals, ie mechanical deformations that add noise.

  Reflectors are more practical for long-term use, but fluctuations in the reflected light caused by fluctuations in blood flow following a heart beat are very small and, moreover, are generally dominated by large amounts of noise.

  For example, the wrist is one of the most convenient positions to wear a reflection sensor for detecting pulses, but it is created, for example, by the movement of tissue under the sensor following the movement of a limb, wrist or finger. Noise on the signal is one of the major obstacles to the optical detection of pulses in this zone. Also, the act of movement or walking generates relative movement of the sensor and the tissue, thereby generating further interference of important features.

  In the art, various solutions have been proposed to try to improve the signal-to-noise ratio during reflection detection in an attempt to filter out the various disturbances superimposed on the useful signal.

  For example, it has been proposed to use a motion sensor arranged with the light sensor in order to detect a relatively large amplitude movement of the body to which the motion sensor is applied. However, this detection device does not provide data on the relative displacement of the sensor and the underlying tissue, and is usually used to prevent the reading of the light sensor in the case of excessive movement of a part of a person Yes, it is assumed a priori that such excessive movement can generate a large amount of interference that can not be filtered effectively. However, in the case of long-term physical activity, when the detection of the heart beat is the one of most interest, the sensor will remain exactly inactive for a long period of time.

  It has also been proposed to use two light sources with appropriate different wavelengths.

  The first wavelength is selected from wavelengths not absorbed by oxyhemoglobin (e.g. red) and the second wavelength is selected from wavelengths better absorbed by oxyhemoglobin (e.g. green). This results in a first signal better associated with tissue movement and a second signal better associated with blood flow. Next, noise filtering is performed by appropriately removing the first signal from the second signal to mitigate the effects of relative motion between the tissue and the sensor. Such a system is described, for example, in EP2462866.

  This type of filtering system provides a noise reduced output signal. However, most often, the signal to noise ratio is still very undesirable. Moreover, the response to a particular selected wavelength does not always remain constant with respect to the passage of time and / or changes in the person receiving the measurement.

  Also, mixed methods provide completely unsatisfactory results. For example, the noise is very large both during running and when working with a computer (finger movement). In the first case the accelerometer is most useful for removing noise, and in the second case it is preferred to use a system with two wavelengths. However, the simultaneous use of both methods proposed in the prior art (e.g. as described in U.S. patent application 2012/150052) only compensates for some noise sources, but is still special It does not provide a satisfactory signal-to-noise ratio in the case of the application or when one is free to perform daily activities. Moreover, the two systems may interfere with each other, further interfering with detection.

  A general object of the present invention is to provide a system which can guarantee a satisfactory detection of the heart beat even in the presence of disturbances caused by various sources. Another object is to provide an innovative system for processing heart rate signals.

  With these goals in mind, the idea devised according to the invention comprises at least one optical reflection sensor unit to be placed on the skin of a person, the sensor unit comprising a light emitter and , A corresponding light receiver for converting light reflected by the skin into an electrical signal, and connected to the light emitter, the light receiver, or both to select the desired wavelength of light in operation Providing an electrically adjustable optical filter, and providing a heart beat detection device.

  Also, this idea is any one of the preceding claims connected by a wireless interface to a data processing and transmission unit that receives data from the device and processes it. The invention was devised to provide a system for detecting and processing physiological data, comprising at least one device as described.

  The idea is also to distinguish between the influence of at least two light wavelengths by means of an electrically adjustable optical filter in order to obtain an electrical signal representative of the heart beat and the corresponding signal received from at least one optical reflection unit. We have devised to provide a method for increasing the signal-to-noise ratio of an electrical signal to detect heart beat optically by at least one optical reflection sensor unit, including processing.

As will become clear from the description and the drawings, the device for detecting or monitoring the heart rate according to the invention can include a sensor system in contact with the skin and in communication with the central processing system. The remote system can include one or more optical detection systems to measure blood volume fluctuations using the physical principles of absorption and fluorescence. This optical system is
-One or more broadband light emitters (e.g. LEDs);
-One or more broadband receivers (e.g. photodiodes or phototransistors);
One or more tunable monochromators, which can be connected to the light emitter, the light receiver, or both to select a specific wavelength;
Can be included.

Also, this heart rate monitor
One or more optical detection systems located at a constant distance along the direction of the blood flow to estimate the propagation time of the blood;
An electrical detection system comprising two or more electrodes in contact with the skin to measure the electrical response of the skin;
A mechanical detection system for measuring the three-dimensional acceleration and orientation of the system;
Can include one or more of

  The heart rate monitor can also foresee that the optical detection system can function in both absorption and fluorescence modes at more than one wavelength by one or more monochromators.

Further in accordance with the present invention, a method for maximizing the signal to noise ratio of a blood volume signal is:
Distinguishing the influence of two (or more) wavelengths in the absorption mode and the fluorescence mode on the signal of the optical detection system;
Dynamically adjusting two (or more) wavelengths to maximize the signal level of the optical detection system;
Can be included.

Besides, this method is
Combining the influence of the absorption mode and the fluorescence mode on the signal of the optical detection system;
Combining the signal from the optical detection system and the signal of the electrical detection system;
Removing the influence of the deformation of the medium on the blood propagation time;
Removing the effects of deformation of the medium resulting from other mechanical influences included in the signal provided by the mechanical detection system;
Can include one or more of

  The heart rate monitor may also include a remote system in contact with the user's skin and in communication with the central processing system.

Also, this remote system
-Remote processor,
A detection system connected to the remote processor;
A remote memory connected to the remote processor;
A clock signal oscillator connected to the remote processor;
A remote user interface connected to the remote processor,
A remote transceiver connected to the remote processor;
A remote antenna connected to the remote transceiver;
A remote processor, a detection system, a remote memory, a clock signal oscillator, and a remote battery connected to the remote transceiver;
Can also include one or more of

Central processing system
-Central processor,
-Central memory connected to the central processor,
A central transceiver connected to the central processor;
A central antenna connected to the central transceiver,
Can be included.

The central memory may further include a set of instructions executable on the central processor, the instructions including:
An algorithm for maximizing the signal-to-noise ratio of the blood volume signal received from the remote system;
An algorithm for processing the blood volume signal optimized to determine a pulsation signal based on the detection of peak values;
including.

  To illustrate the innovative principles of the present invention and their advantages as compared to the prior art, examples of embodiments to which these principles apply are described below with the help of the accompanying drawings.

Fig. 2 shows a block diagram of a first reflection detection device provided according to the principles of the present invention. Fig. 3 shows a graph of the signal detected by the device according to the invention. Fig. 5 shows a block diagram of a second reflection detection device provided according to the principles of the present invention. Fig. 6 shows another graph showing the signal detected by the device according to the invention. Fig. 3 shows a block diagram of a possible system for remote processing of data detected by a sensor according to the invention. FIG. 1 shows a schematic of a bracelet detection system and an intelligent portable terminal for processing (or initial processing) of detected signals.

  With reference to the drawings, FIG. 1 shows a first reflection detector according to the invention for detecting a heart beat.

  Such a detector, generally indicated by 10, comprises the light emitter 11 (e.g. an LED diode emitter) and the light of the emitter 11 after reflection on the skin 13 of a person undergoing heart rate detection. And a corresponding light receiver 12 (eg, a photodiode or phototransistor). Advantageously, as will be clarified below, the detector or device 10 can be positioned on the back of the wrist, for example like a watch.

  The light receiver 12 converts the received light into an electrical signal that is sent to the electronic processing block 14, which is also referred to as the corresponding signal 15 (BVP (i.e. blood volume pulse) signal) that is dependent on the human heart rate. Send out). Block 14 may be a combination of analog amplification circuitry and a programmable microprocessor device for processing the signal, as can be readily imagined by one of ordinary skill in the art in view of the description provided herein.

  Advantageously, the light emitter 11 emits a broad spectrum of light (e.g. white light) and the device 10 is an adjustable optical filter 16 and / or arranged in front of the transmitter 11 and the light receiver 12, respectively. An adjustable optical filter 17 is included. These optical filters can be controlled by the processing block 14 to be tuned to the desired wavelength to filter the transmitted and / or reflected light.

  Advantageously, these optical filters include so-called "monochromators", which allow dynamic selection of specific wavelengths from broad spectrum light. In particular, it has proven to be advantageous to use adjustable Fabry-Perot monochromators, which are essentially known and can be easily miniaturized.

  Also advantageously, the apparatus can include a circuit 18 for powering the light emitter 11, which is controlled by the processing block 14 to adjust the luminous intensity of the light emitter 11 to a desired value.

  The apparatus 10 may also include a known accelerometer 19 for sending motion signals to the processing block 14 for reasons that will become clear below. Advantageously, an accelerometer is selected to measure the three-dimensional acceleration and orientation of the system.

  As is known, oxyhemoglobin present in blood absorbs a given wavelength. This effect is called "absorption".

  Moreover, oxyhemoglobin re-releases some of the absorbed energy in the form of light of a different wavelength than that absorbed. This effect is called "fluorescence".

  By using adjustable filters, it is possible to configure the system to use one effect first and then the other. In the first mode, a wavelength is provided that maximizes absorption, and the same wavelength is "observed" by the light receiver 12. In the second mode, a wavelength that maximizes fluorescence emission is provided, and the fluorescence emission wavelength unique to oxyhemoglobin (a wavelength that is always greater than the incident wavelength for energy balance) is observed by the light receiver 11.

  It is possible to improve the signal-to-noise ratio by combining the signals read by the receiver in two different modes: "absorption" mode and "fluorescence" mode.

  Moreover, the filter is adjustable so that it emits fluorescence and / or on the characteristics of the skin of the person whose heart beat is being detected (eg age, degree of sunburn, skin color, presence of fat, presence of body hair). Or it is possible to adapt the absorption wavelength.

  In fact, the skin located between the detector and the oxyhemoglobin produces optical interference which can degrade the emitted and / or received light. Therefore, it may be useful to try to find a wavelength that maximizes the amplitude of the BVP signal, depending on the characteristics of the skin, whether in fluorescence or absorption mode, perhaps whenever the device is turned on I know.

  For example, extremely fair skin favors the penetration of light, so that in the absorption mode wavelengths near the UV band can be used effectively. On the contrary, with tanned or dark skin, small wavelengths can not reach the receiver unless the intensity is such as to adversely affect battery life.

  A similar situation exists in the fluorescence mode, where the stimulation in the purple-blue band and the detection in the orange band give the maximum response of oxyhemoglobin.

  In other words, during operation, the processing block 14 uses wavelengths that are considered suitable for detecting heart beats using the “absorption” method (eg 530-580 nm for very dark skin, very The filter can be adjusted to the range of 410 to 450 nm in the case of the skin of the skin, and the corresponding signal reflected and captured by the light receiver 12 can be obtained. Also, processing block 14 may use wavelengths that are considered suitable for detecting heart beats using the “fluorescent” method (eg, 410-450 nm for emission filters, 590-630 nm for light-receiving filters) The filter may be adjusted to obtain the corresponding fluorescence signal captured by the light receiver 12). By superimposing the two signals received (with appropriate compensation for the time delay between the two measurements), it is possible to obtain a BVP signal having an amplitude greater than the background noise.

  Moreover, the device can be operated during two measurements (or, advantageously, during a calibration step that may occur when the device is turned on after application to the skin, or periodically during operation) In an attempt to maximize the peaks of the signal received in the two modes, it is possible to change the wavelength of the filter in the region of the fundamental wavelength defined for fluorescence and absorption. After defining the wavelengths at which a larger signal is obtained, the device can use these wavelengths for subsequent measurements until a subsequent calibration operation is performed.

  By repeating the calibration periodically during operation of the device it is also possible to compensate for variable conditions of the skin which may affect the measurement (e.g. fluctuations in the degree of sunburn, sweating or temperature changes) .

  Another advantage is to compensate, for example, for disturbances of the signals due to relative movement of the skin and the device caused by movements of the person or muscles and tendons of the zone of the body in which the sensor is arranged (eg finger movements). Is also possible. In fact, the light emitted by the light emitter 11 is less sensitive to the blood flow, but by a wavelength more sensitive to movement on or under the skin (e.g. wavelength 650-750 nm) As characterized, it is possible to adjust the filters (or, in the case of a device with both filters, a plurality of filters). The corresponding signal captured by the detector 12 is used by the processing block 14 as a noise signal to be removed from the electrical signal obtained by detection of the BVP signal via an adaptive numerical filter to remove significant noise components. be able to.

  Filtering is also performed to select substantially green or red light for use in the prior art, or to filter in the infrared range or otherwise (using an appropriate light emitter) be able to.

  Advantageously, the detector 10 also uses the signal provided by the accelerometer 19 to compensate for disturbances due to significant movement of the device (e.g. as a result of physical activity performed by a person) it can. The accelerometer signal may be provided to block 14 to provide an adaptive numerical filter that intervenes in the case of sudden acceleration (e.g., when driving).

  The accelerometer 19 signal has an acceleration detected from a threshold previously determined to correspond to a motion noise source that is too large for effective compensation of noise on the BVP detected by the optical system. If larger, it can also be used to prevent the emission of BVP signals by the device.

  In order to reduce noise on the output signal, the device 10 can also advantageously influence the intensity of the light emitted by the sensor 11. However, in the case of battery-powered devices, greater light intensity can negatively impact the duration of battery charging.

  FIG. 2 shows a graph schematically illustrating the relationship between light E (axis X) emitted by the light emitter and the amplitude R (axis Y) of the received signal.

  As can be seen from the graph, there is an essentially linear relationship between the emitted light and the reflected light measured by the receiver. Thus, both noise or BR (background reflection) and BPR (blood pulse reflection) signals, which may also include ambient light captured by the sensor, increase with increasing luminous intensity E. The slopes of the two straight lines in the graph define the light reflection curve and can be varied by people.

  In any of the above, in the case of a specific radiation E, the first person may have a specific dR (i.e. a specific amplitude dR of the periodic variation of the reflected light transmitting blood pulsation information) Means The second person may have a value dR that is less than or greater than the first person's value dR for the same value E.

  If the value dRmin (i.e. the received minimum useful signal value) is established, the light emitter is advantageously arranged by the block 14 to have a radiation E which can keep the signal dR above the value dRmin in any case. It is controlled. While it is possible to emit light constantly at certain values (eg 1000 mcd) to ensure that this condition is always present, such a solution results in unnecessary premature wear of battery power there is a possibility.

Advantageously, it is preferable, instead, that the signal dR always always be just slightly higher than the value dRmin. Thus, a value of E is obtained, which can be called Eopt (ie E-optimal), which satisfies this condition and is variable depending on the person or on different conditions of the person. Both are shown by way of example in FIG. 2 (Eopt1 and Eopt2 give the same dR ₁ = dR ₂ = dRmin for _two samples).

  Thus, as described above, block 14 optimizes the amplitude of the useful signal while at the same time keeping the signal dR slightly higher than dRmin (optionally with a small safety margin) to maximize battery life. The radiation E can be advantageously varied by means of the power supply element 18.

  Thus, it is also possible to use high intensity light emitters (LEDs) in a battery system, using higher light emission only for the required time if necessary.

  It is also possible to provide the power supply of the source alternately in a pulsed manner and / or between the light emitters both for reducing battery consumption and for sharing some or all of the drive circuits between the light emitters.

  FIG. 3 shows a second embodiment of a detector according to the invention. In this second embodiment, generally designated 110, two detectors or devices 10, designated as 10a and 10b as described above, are used and their BVP signal outputs 15a and 15b are processing comparison blocks It is further processed by 120.

  The two detectors 10a and 10b are generally arranged along the main direction of the blood flow in the part of the body where the device 110 is positioned, corresponding optical units (light emitter 11, light receiver 12, and any (Formed by optical filters 16 and / or 17). For example, when positioning on the limb, the direction is along the axis of the limb itself. In particular, when positioning on the wrist, the direction can advantageously be from elbow to hand.

  The distance between the optical units can be a few centimeters or less, depending on the sensitivity of the detector and the position chosen on the body.

  By using the two devices 10a and 10b, two signals 15a and 15b which are slightly out of phase with one another (depending on the mutual distance) are obtained, as schematically shown in FIG.

  By calculating the correlation of the time variation of the two signals performed by block 120, it is possible to calculate the time "delta t" of the passage of blood between the two optical units.

  By detecting this temporal variation (or the apparent velocity of blood displacement between the two optical units) it is possible to obtain information about the movement of the tissue under and between the two optical units I know. In other words, these movements can change the length of the blood vessel and thus change the detected velocity values or, rather, the transit time between two optical units (at a constant distance from one another) I know that.

  Thus, it is possible to obtain other information about the noise generated by the muscle movement and which can be removed from the BVP signal to obtain an improved BVP signal at the output 121 of the processing block 120.

  Advantageously, the device 110 also preferably includes a system for measuring the conductivity of the skin in the ventral zone of the wrist having significant cutaneous electrical activity.

  The system for measuring the conductivity (or the electrical effect of the skin) is advantageously connected to a measuring block 124 which contacts the skin in the selected zone and detects the electrical resistance between the two electrodes And two metal electrodes 122 and 123.

  The measurement of resistance can be performed simply by letting low or very low current flow across the skin. A compensation algorithm can also be used to control the current flowing through the skin so as to balance the reference line for that person and make it a zero line. The power supply on the electrodes can be periodically reversed to avoid polarization and / or electrolysis phenomena. Moreover, the electrodes can be lined with silver to prevent possible damage to the skin and deterioration of the electrodes.

  The reversal of polarity dramatically reduces the risk of depositing Ag + ions on the outer layer of the skin. The ions that may have been deposited on the skin are once again bound to the surface of the electrode each time the polarity is reversed.

  The resistance value measured by the detector is present on the output 125 of the block 124 and further processing of the BVP signal 121 is performed to further reduce the noise associated with it using the variation in conductivity at the output 125 To another processing block 126 to

  In fact, it has been found that the variation in conductivity measured on the skin in the area of the optical unit has a similar progression to BVP added to the slow progression of perspiration. The observed variation in conductivity, as with BVP, is particularly due to blood waves that travel along superficial blood vessels and tend to contract the sweat glands that release small amounts of fluid at the same frequency as the heart beat.

  This signal is generally very small and can not easily be used alone to obtain an indication of the heart rate, but when combined with the optically detected signal as described above, according to the invention The signal to noise ratio of the BVP signal output by the device can be further improved.

  Although not shown in FIG. 1, this system for measuring the conductivity has the signal 15 of block 14 (in place of the signal 121 of block 120) at its input, as can easily be imagined by the person skilled in the art The processing block 125 sent can be used equally in the device 10 according to FIG. 1 to reduce noise.

  As shown by way of example by the dashed line 127 in FIG. 3, the slow variation of the skin's conductivity can be used to provide the device 110 (or such conductivity) for use in providing other physiological information about the person. It can also be sent outside the device 10) that uses the detector.

  The device 110 can also use an accelerometer 19 as described for the device of FIG. The accelerometer is advantageously connected in this case to the last processing block 126 located before the BVP signal output 128 of the device. Either of the devices 10 and 110 sends a three-dimensional acceleration signal to the outside for use in providing other information about the person, as illustrated by the dashed lines 20 and 129 in FIGS. 1 and 3 by way of example. It can also be done.

  FIG. 5 schematically illustrates an advantageous and complete system, generally designated 200, for detecting and processing human physiological data.

  System 200 includes a remote device 201 that includes a detector of the same type as detector 10 or 110 described herein, the detector's BVP signal (15 or 128) and any conductivity signal 127 being It is sent to the data processing transmission unit 202.

  This unit 202 is advantageously formed as a suitably programmed microprocessor unit, and thus, a processor 203 receiving signals from the device 10, 110, a program memory 204 connected to the processor 203, and a data memory 205. And the transmission unit 206 advantageously.

  The unit 202 can be integrated into the remote device 201 or designed entirely or partly as a separate device, a known system (eg touch screen type) for introducing commands and displaying data and information Can also be included).

  The unit 202 is designed to communicate with the remote server 208 which may be in communication with one or more terminals 209 (advantageously via a wireless or mobile telephone connection for connection to the Internet) be able to.

  In this way, physiological data processed or preprocessed by the device 201 can be sent to the remote display control terminal 209 (also after further processing by the server 208). Thus, remote inspection of the person wearing the device 201 is possible. The data processed by the server (or by the remote terminal 209 at the time of operation by the operator) can be sent to the unit 202 for local display, for example by the person whose measurement is being performed.

  The signals 15, 128 and 127 can be sent directly to the unit 202 or exchanged via a communication interface 207 (wired or advantageously of the wireless type) which is essentially known.

  In the case of a wireless connection, the detector 10, 110 is a small portable device (eg, in the form of a watch) held in the pocket or in wireless communication with the hand-held processing communication unit 202, along with a suitable communication interface 207. Can be incorporated into

  FIG. 6 shows an advantageous embodiment of the device 201 according to FIG. In this embodiment, the detector 10, 110 is designed in the form of a device 210 to be worn on the wrist, the light sensor being placed in contact with the skin when the device is fixed to the wrist by the strap 211 Is placed on the side that is intended. Preferably, an electrical sensor is arranged on the strap itself. Advantageously, a seal ring 212 can be provided around the light sensor and pressed against the skin to prevent ambient light and / or external moisture from entering the area monitored by the sensor.

  The device 210 can be wirelessly (e.g. advantageously low energy Bluetooth) wirelessly with an intelligent terminal (preferably a smart phone or tablet etc) that performs the functions of the processing communication unit 202, with appropriate programming that can be easily imagined Communicate via a type interface 207). The terminal may communicate with the Internet or a cellular network wirelessly as described above if remote processing or display of data is required.

  The input of commands and the display of information can be easily performed at that location by the touch screen 213 of the terminal 202.

  An interesting application of the system shown in FIG. 5 and / or FIG. 6 is the level of stress conditions, physical activity and conditions for the person wearing the device 210 and / or the remote operator via the terminal 209. It may be an application example showing various physiological parameters such as sleep quality, excitement level and so on. These parameters can be determined on the basis of the signal detected by the device 210. The operator can also receive data from multiple remote detectors worn by multiple people.

  At this point it is clear how the predefined objectives have been achieved. Using the method and apparatus according to the invention, it is possible to obtain a precise and reliable signal in many conditions where interference is present. For example, while switching between absorption and fluorescence modes, it is possible to select the color of the light depending on the external conditions and the condition and type of skin and to change the operating mode of the system.

  The heart rate monitor according to the invention can advantageously include a sensor system in contact with the skin and in communication with the central processing system. Moreover, the sensor system can include one or more optical detection systems for measuring blood volume fluctuations using the physical principle of absorption and / or fluorescence. The optical system includes one or more broadband emitters (LEDs) and one or more broadband receivers, and one or more connected to the emitters, the receivers, or both to select a particular wavelength. And advantageously an adjustable monochromator filter.

  By the principles of the present invention, it is possible to eliminate the effect of tissue deformation on blood propagation time, if necessary. The propagation speed is partially altered by the pulse itself but is further altered by stretching the tissue. By appropriate use of the signals obtained by the described system it is possible to remove other noise components. Moreover, if necessary, it is possible to eliminate the effects of "macroscopic" movement measured by the accelerometer. It is also possible to use high intensity light emitters effectively.

  Clearly, the description provided above for the embodiments applying the innovative principles of the present invention is provided as an example of these innovative principles, and thus, the claimed right of the present invention. It should not be considered as limiting the scope.

  For example, the various processing blocks described above as discrete may be combined with one another into a single processing block (e.g., a suitably programmed microcontroller unit), as can be readily imagined by one skilled in the art. It can also be done. For example, block 14 of detector 10 or two detectors 10a and 10b may be designed as a single processing block, which may also include block 120 and possibly blocks 124 and 126. Advantageously, the various blocks are algorithms for controlling the optical detection system during absorption mode and for receiving signals from the optical detection system, for controlling the optical detection system during fluorescence mode and for receiving signals from the optical detection system Algorithms for controlling the system for detection of skin conductivity, algorithms for receiving signals from the system for detecting skin conductivity, and systems for detecting acceleration (or mechanical movement) A plurality of algorithms may be implemented including at least one of: an algorithm for receiving signals from an acceleration detection system.

  These algorithms can be implemented by means of suitable programs that can be executed by the processor included in the device according to the invention, as can be imagined by the person skilled in the art on the basis of this description. Advantageously, any of the filters can be adaptive numerical filters.

  In the case of remote transmission, an algorithm for encoding a signal received from one or more detection devices for its transmission to an external processing unit via the transceiver of the device, as well as from an external processing unit via the transceiver It is also possible to foresee an algorithm for decoding the received signal. Another program portion may manage status commands for controlling a status light (eg, an LED) on the user interface of the device.

  The system using filters selectable for the wavelength of light uses signals obtained at more than two wavelengths (eg blue, green, infrared) to optimize certain aspects of the detection operation, It is also possible to compare and process.

  The various innovative solutions according to the invention described as being incorporated simultaneously into the examples of the above embodiments can also be used individually in the device and system according to the invention or in different combinations. it can.

The device according to the invention (e.g. that of its device configuration 210) is connected to a tri-color status light (LED) connected to the processor to indicate system status and a remote processor to talk to the detection device Other elements useful for the actual operation, such as buttons, may also be included. The status indicated by the status indicator can be at least one of low battery, during battery charging, and data acquisition mode. The device can also include a port for charging the internal battery.

Claims (18)

At least one optical reflection sensor unit (10) to be arranged on the skin of a person, said sensor unit comprising a light emitter (11) and corresponding light reception converting light reflected by said skin into an electrical signal A heart beat detection device provided with
A heart beat, characterized in that it comprises electrically adjustable optical filters (16, 17) connected to the light emitter, the light receiver, or both to select the desired wavelength of the light in operation. Detection device.   The device according to claim 1, characterized in that the electrically adjustable filter (16, 17) comprises a Fabry-Perot monochromator.   A mode for measuring a first signal dependent on blood volume fluctuations using the physical principle of receiving the signal from the light receiver and absorption of the blood volume using the physical principle of fluorescence. Alternately selecting the mode for measuring the second signal that is dependent on the variation, and the filter (for processing the first and second signals to obtain a signal representing the heart rate (15) The device according to claim 1, characterized in that it comprises a processing unit (14) for controlling 16, 17).   A processing block (14) according to claim 1, characterized in that it comprises a processing block (14) for controlling the filter (16, 17) in order to receive the signal from the light receiver and optimize the amplitude of the received useful signal. Device.   The apparatus includes two light sensor units (10a, 10b) arranged at a distance from each other and connected to a signal processing block (120) to estimate blood propagation time between two units, said processing block comprising The apparatus according to claim 1, characterized in that the signal detected by the at least one optical unit is changed according to the fluctuation of the estimation time.   An electrical detection system (122, 123, 124) for measuring the electrical response of the skin, and from this measurement a signal dependent on the heart rate is determined, this signal and the signal detected by the at least one optical unit A device according to claim 1, characterized in that it comprises: a processing block (126) coupling together.   A system (19) for measuring the acceleration of the device, and a processing block (14, 126) for modifying the signal detected by the at least one optical unit depending on the measurement. The device according to claim 1.   For processing the signal received from the light receiver (12) to change the luminous intensity of the light emitter in order to maintain the received useful signal above a predefined minimum threshold value Device according to claim 1, characterized in that it comprises a power supply element (18) for the light emitter (11) of the at least one optical unit receiving a command from a block (14).   9. At least one device according to any of the preceding claims, connected by a wireless interface (207) to a data processing and transmission unit (202) receiving data from the device and processing it. System for detecting and processing dynamic data.   The system according to claim 9, characterized in that said processing and transmission unit (202) communicates with a remote terminal (209).   The system according to claim 10, characterized in that said processing transmission unit (202) communicates with said remote terminal (209) via the Internet.   A device according to claim 9, characterized in that the device is in the form of a device (210) to be fixed to the wrist by a strap, and the processing transmission unit (202) is a suitably programmed tablet or smartphone. system.   Distinguishing the influence of at least two light wavelengths by means of an electrically adjustable optical filter by means of an adaptive numerical filter and processing the corresponding signals received from at least one optical reflection unit in order to obtain an electrical signal representative of the heart beat A method for increasing the signal-to-noise ratio of the electrical signal to optically detect the heart beat by the at least one optical reflectance sensor unit.   The at least two wavelengths are selected to have an absorption mode and a fluorescence emission mode for the signal of the detection unit, and the two (or more) wavelengths are maximized to maximize the signal level of the optical unit. 14. The method of claim 13, wherein the filter is adjusted to adjust dynamically.   In order to detect the time difference between the received signals and to estimate the blood propagation time between the two units, and to vary the signals detected by the at least one optical unit depending on the variation of the estimated time The method according to claim 13, wherein two optical units arranged at a distance from each other are used.   The method according to claim 13, wherein a three-dimensional acceleration signal is obtained, which signal is removed from the signal detected by the at least one optical unit by means of an adaptive numerical filter.   The method according to claim 13, wherein the electrical response of the skin is measured, a signal dependent on the heart rate is obtained therefrom, and this signal is combined with the signal detected by the at least one optical unit. 14. The electrical signal representing the heart beat is used to estimate various physiological parameters of a person, such as stress status, level of physical activity and condition, quality of sleep and / or excitement level. Method described.

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